Enabling TSN Capabilities in Open RAN over Converged XHaul Networks

• Grant number: 25/04041-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: April 01, 2025
• End date: March 31, 2029
• Field of knowledge: Engineering - Electrical Engineering - Telecommunications
• Principal Investigator: Christian Rodolfo Esteve Rothenberg
• Grantee: Sérgio Rossi Brito da Silva
• Host Institution: Faculdade de Engenharia Elétrica e de Computação (FEEC). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Company: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Elétrica e de Computação (FEEC)
• Associated research grant: 21/00199-8 - SMART NEtworks and ServiceS for 2030 (SMARTNESS), AP.PCPE

Abstract

The Open Radio Access Network (O-RAN) architecture, defined by the O-RAN Alliance, a consortiumformed by a diverse group of mobile network operators, infrastructure vendors, and software developers,has as one of its main objectives the establishment of a new telecom paradigm based on an open,intelligent, interoperable, and virtualized RAN. These characteristics can drive a transformative shift inmobile communications by delivering a flexible, scalable, and cost-effective architecture, which may becritical for enabling Beyond 5G (B5G) and 6G networks. However, the adoption of O-RAN compliantnetworks by the Mobile Network Operators (MNOs) still present challenges, such as the use of openinterfaces that go hand in hand with RAN disaggregation, leading to infrastructures where RAN nodes areinterconnected by transport networks composed not only of dedicated fiber segments but also of legacyand other diverse network infrastructures. This results in a complex and heterogeneous scenario, wherefixed and mobile traffic converge, forming what is commonly referred to as a converged XHaul network,integrating fronthaul, midhaul, and backhaul alongside other media access technologies.In this context, assuring low latency and high reliability for emerging applications running on top ofsuch converged XHaul interconnecting multiple RAN nodes is a highly complex undertaking. Additionally,synchronization errors may render its operation unfeasible. To address these issues, Time-SensitiveNetworking (TSN) features have been proposed for integration into the O-RAN architecture, particularlythose defined by IEEE 802.1CM, IEEE 802.1Qbu, and IEEE 802.1Qbv. Nevertheless, these features arenot widely available in Ethernet switches, as their implementation raises hardware costs, counteracting oneof O-RAN's fundamental principles: protecting Capital Expenditures (CAPEX) and reducing the Total Costof Ownership (TCO).This research project aims to integrate TSN features into the O-RAN architecture to address keychallenges within the disaggregated and heterogeneous O-RAN transport network. Specifically, deployingTSN features in a software-based transport network is expected to achieve a level of determinismcomparable to that of bare-metal TSN networks, without requiring specialized hardware. Additionally,we explore efficient resource scheduling strategies within the XHaul to handle this heterogeneity, usingtechnologies such as network slicing. The proposed solutions will be validated through simulations usingdiscrete-event simulators and experimental evaluations leveraging programmable network devices, suchas Intel Tofino switches